It is known in the art to form a package with composite packaging film where the film is first transversely slotted at package length intervals and then applying a strip from a roll of adhesively coated film pressed onto it covering over the previously cut slot. The composite film is then fed into a packaging machine or wound onto a take-up roll for future use. Such technology is described for example in U.S. Pat. No. 5,983,594 entitled “Adhesively Peelable Package Method and Apparatus” issued to Harold J. Forman. In that system, adhesive tape secures the bag in a closed position by adhering the front of the bag to the inside rear wall of the bag by contact with the sealing tape through the slot.
U.S. Pat. No. 6,254,519 issued to Isao Toshima entitled “Tape Sealed Bag and Method for Producing the Same” discloses flexible packaging wherein a preformed slit in the supply film is first covered by placing a fusing tape over the slit. A weld is then placed around the perimeter of the slit to obtain a positive seal to the bag. The slit is positioned below the top edge of the bag which is then heat sealed to form the top end wall of the bag. Additional welds are placed at the rear of the bag on wraparound ends of the fusing tape. The high yield strength of the weld provides the positive package sealing while a low yield strength adhesive of the tape provides easy opening and reclosing after the welds are burst on the initial package opening. The burst welds serve to indicate that the package has been previously opened.
U.S. Pat. No. 4,709,399 issued to Sanders entitled “Opening Facilitating Closure Tape and Container” discloses a peel-down tape which covers a lateral package opening slit. This document discloses the use of corona discharge for a means of treating either the tape or the web to affect adhesion.
A problem with the prior art is that forming the slit in the web prior to applying the opening tape weakens the film strength and reduces the allowable amount of feed tension below that which is necessary for rapid production. Also, because the opening is below the top of the bag, contents of the bag accumulate in the pocket between the top of the opening and the top of the bag and interfere with reclosing.
There is therefore a need in the art to overcome the above-described disadvantages of the prior art packaging and to provide an easy-open resealable package which may be rapidly produced by permitting a higher speed production rate.